Chevrolet 1977 light duty truck, Service Manual

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m o u n t and its attaching point, tighten the screws or nuts
attaching the m ount to the transmission or crossmember.
Front Mount Replacement
1. Remove engine m ount through bolt.
2. Raise engine and remove m ount to fram e
bracket attaching bolts. R em ove mount.
CAUTION: Raise engine only enough fo r
sufficient clearance. Check fo r interference
between rear o f engine a n d cowl panel.
3. Install new engine m ount to fra m e bracket and
torque attaching bolts to specifications.
4. Install engine m o u n t thro u g h bolt and torque to
specification.
Rear Mount Replacement
1. Sup p o rt engine weight to relieve re a r mounts.
2. Remove crossm em ber-to-m ount bolts.
3. O n P Series with m a n u a l transmission and
propeller shaft p ra k in g brake, remove m ount attaching
bolts from f r a m e outrigger and clutch housing and
remove re a r m o u n tin g cushions.
4. R em o v e m o u n t-to -tra n s m is s io n bolts, then
remove mount.
5. O n P Series with m anual transmission and
propeller shaft p ark in g brake, install new m ounting
cushions and bolts.
6. Install new m ount on transm ission.
7. W hile lowering transmission, align and start
crossm em ber-to-m ount bolts.
8. T orque bolts to specifications then bend lock
tabs to bolt head as applicable.
M A N IF O L D ASSEMBLY - N O N -IN T E G R A T E D
HEAD
Removal
1. Remove air cleaner.
2. Disconnect both throttle controls at bellcrank
and remove throttle return spring.
3. Disconnect fuel and vacuum lines at carburetor.
4. Disconnect crankcase ventilation hose at rocker
arm cover.
5. Disconnect vap o r hose at canister.
6. Disconnect exhaust pipe at m anifold flange and
discard packing.
7. Rem ove m anifold attaching bolts and clamps
then rem ove m an ifo ld assembly and discard gaskets.
8. Check fo r cracks in m anifold castings.
9. Separate m anifold by rem oving one bolt and
two nuts at center o f assembly.
Installation
1. C lean gasket surfaces on cylinder head and
manifolds.
2. Lay a straight edge along the full length o f the
exhaust port faces and m easure any gaps between the
straight edge and the port faces. I f at any p oint a gap o f
.030 or m ore exists, it is likely that the m anifold has
distorted to a point where it will not seat properly. If a
good exhaust seal is to be expected, the exhaust m anifold
must be replaced.
3. Reinstall the one bolt and two nuts at the center
o f the m anifold to finger tight.
4. Position a new gasket over m anifold end studs
on the cylinder head.
5. Install m anifold assembly bolts and clamps
while holding m anifold assembly in place by hand.
6. Clean, oil and torque all m an ifo ld assembly to
cylinder head bolts and nuts to 35 lbs. ft.
7. Complete torquing the inlet to exhaust m anifold
bolt and two nuts at the center o f the m anifold to 30 lb.
ft.
8. Connect exhaust pipe to m anifold using a new
packing.
9. Connect crankcase ventilation hose at rocker
arm cover.
10. Connect vapor hoses at canister.
11. Connect fuel and vacuum lines a carburetor.
12. Connect throttle controls at bellcrank and
install throttle return spring.
13. Install air cleaner, start engine, check for leaks
and adjust carb u reto r idle speed.
E XH A U S T M A N IF O L D ASSEMBLY -
IN T E G R A T E D HEAD
Removal
1. Disconnect negative battery cable.
2. Remove air cleaner.
3. Remove power steering p u m p a n d / o r A.I.R.
p u m p brackets, if so equipped.
4. Raise vehicle on hoist and disconnect exhaust
pipe at manifold and converter bracket at transmission
mount. If equipped with manifold converter, disconnect
exhaust pipe from converter, remove converter.
5. Lower vehicle.
6. Remove re a r heat shield and accelerator cable
bracket.
7. Remove exhaust m anifold bolts.
8. Remove exhaust m anifold, check EFE Valve to
see if free and check manifold for cracks.
Installation
NOTE: If a new exhaust m anifold is being
installed, the E.F.E. valve an d actuator and rod
assembly must be transferred from
the old
component.
1. Clean gasket surface and position new gasket on
exhaust manifold.
2. Install m anifold bolts, while holding manifold
assembly in place.
3. Torque all cylinder head to m anifold bolts to
specifications (Fig. 6 A -1 1).
4. Install re a r heat shield and accelerator cable
bracket.
5. Raise vehicle on hoist.
6. Connect exhaust pipe at m anifold flange and
converter bracket at transmission mount. If equipped
with m a n ifo ld converter, loosely install M a n ifo ld